netlink: 6 bytes leftover after parsing attributes in process `syz-executor2'. netlink: 6 bytes leftover after parsing attributes in process `syz-executor2'. ================================================================== BUG: KMSAN: uninit-value in copy_to_user include/linux/uaccess.h:184 [inline] BUG: KMSAN: uninit-value in move_addr_to_user+0x32e/0x530 net/socket.c:227 CPU: 1 PID: 8762 Comm: syz-executor5 Not tainted 4.16.0+ #87 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x185/0x1d0 lib/dump_stack.c:53 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067 kmsan_internal_check_memory+0x135/0x1e0 mm/kmsan/kmsan.c:1157 kmsan_copy_to_user+0x69/0x160 mm/kmsan/kmsan.c:1199 copy_to_user include/linux/uaccess.h:184 [inline] move_addr_to_user+0x32e/0x530 net/socket.c:227 ___sys_recvmsg+0x4e2/0x810 net/socket.c:2211 __sys_recvmmsg+0x54e/0xdb0 net/socket.c:2313 SYSC_recvmmsg+0x212/0x3e0 net/socket.c:2389 SyS_recvmmsg+0x76/0xa0 net/socket.c:2378 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 RIP: 0033:0x455389 RSP: 002b:00007f725fa3cc68 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00007f725fa3d6d4 RCX: 0000000000455389 RDX: 000000000000000a RSI: 0000000020006180 RDI: 0000000000000014 RBP: 000000000072bf58 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000002000 R11: 0000000000000246 R12: 00000000ffffffff R13: 000000000000049e R14: 00000000006f9f70 R15: 0000000000000001 Local variable description: ----addr@___sys_recvmsg Variable was created at: ___sys_recvmsg+0xd5/0x810 net/socket.c:2172 __sys_recvmmsg+0x54e/0xdb0 net/socket.c:2313 Byte 19 of 32 is uninitialized ==================================================================